Bacterial endophytes in agricultural crops and their role in stress tolerance: a review

Abstract

Bacterial endophytes are a class of endosymbiotic microorganisms widespread among plants that colonize intercellular and intracellular spaces of all plant compartments and do not cause plant disease or significant morphological changes. Plant and endophytic bacteria association includes vast diversity of bacterial taxa and plant hosts and in this review we present an overview of taxonomic composition of endophytes identified in common agricultural crops. Further, during the last decade, new aspects of the microbial diversity have emerged with application of new metagenomic analysis methods in studies of bacterial endophytes. Endophytic bacteria community structure is influenced by plant genotype, abiotic and biotic factors such as environment conditions, microbe -microbe interactions and plant -microbe interactions. Agricultural practices, such as soil tillage, irrigation, use of pesticides and fertilizers have a major effect on function and structure of soil and endophytic microbial populations. Therefore, the use of agricultural practices that maintain natural diversity of plant endophytic bacteria is becoming an important element of sustainable agriculture that could ensure plant productivity and quality of agricultural production. The diverse endophytic microbial communities play integral and unique role in the functioning of agroecosystems. Endophytic bacteria have been shown to have several beneficial effects on their host plant, including growth promoting activity, modulation of plant metabolism and phytohormone signalling that leads to adaptation to environmental abiotic or biotic stress. Use of endophytic bacteria presents a special interest for development of agricultural applications that ensure improved crop performance under cold, draught or contaminated soil stress conditions or enhanced disease resistance.

Effect of osmoprotectants on the survival of bacterial endophytes in lyophilized beet roots

“…In general, endophytic microbiome diversity and composition is related to soil properties as well as plant ecology and physiology (Miliute et al, 2015). Members of only three phyla (Proteobacteria, Actinobacteria and Firmicutes) were cultured in our experiment, this may be related to their high ability to grow on commercially available media (Milute et al, 2015; Szymańska et al 2016a, Szymańska et al 2016b; Brígido et al, 2019).…”

The impact of microbes in the orchestration of plants’ resistance to biotic stress: a disease management approach

“…The endophytes will continue to enjoy the aid the plants render to them until the plant is mechanically uprooted or die; however, during the life of the plant, both parties benefit (Miliute et al 2015). The presence of these organisms does not, in any way, interrupt the proper functioning of the plant and so they are not pathogenic.…”

ISOLASI DAN KARAKTERISASI BAKTERI ENDOFIT TANAMAN TOMAT CHERRY (Solanum lycopersicum var. cerasiforme) DALAM KEMAMPUANNYA MENGHASILKAN HORMON ASAM INDOL ASETAT (AIA)

“…Sebanyak 1 mL supernatan ditambah dengan 2 mL reagen Salkowski (0,5 M FeCl3 dan 70% asam perklorat) (Gordon & Weber, 1951 Keberagaman ini salah satunya dipengaruhi oleh kondisi pertumbuhan tanaman (Purwanto et al, 2014). Umumnya bakteri endofit yang mudah dikultur pada medium pertumbuhan sintetis berasal dari Proteobacteria, sedangkan Firmicutes, Actinobacteria dan Bacteriodes lebih sulit (Miliute et al, 2015).…”